1. Field of the Invention
The invention relates to an image reading apparatus for reading film images. In particular, the invention relates to an image reading apparatus that can handle films having different sizes.
2. Description of Related Art
A film scanner is an image reading apparatus for reading film images provided on film photographed by a camera, for example. The film scanner reads images provided on negative film or on reversal film under the control of a host computer and outputs those images to the host computer. The host computer displays the film images on a monitor screen.
With 35 mm film, a user receives developed film in strip or mounted form (e.g., slides). In the latter case, a film scanner is used for the purpose of reading the images provided on the film received on slide mounts. In the case of strip film, the film scanner reads those images by receiving the film in a custom holder.
Recently, new standards have been proposed whereby long-type film (“roll film”) is handled while it is housed in a cartridge. With this film system, the film is in a photography-enabled state simply by loading the cartridge into the camera. Additionally, when the film is developed, the user receives a cartridge housing the developed film (rather than receiving the developed film without a cartridge).
A conventional film scanner cannot read the images of the roll film housed in the cartridge. Consequently, new types of film scanners have been proposed (see, for example, Japanese Laid-Open Patent Application No. 5-75922), whereby the images on roll film housed in a cartridge can be read.
One type of film scanner uses a line sensor having a plurality of photoelectric converters arranged in a row. A second type of film scanner uses an area sensor having a plurality of photoelectric converters arranged in rows and columns (i.e., a matrix). Japanese Laid-Open Patent Application No. 5-75922 uses an area sensor.